1.3.1

Momentum

Test yourself

Momentum and Impulse

The momentum of an object is its mass multiplied by its velocity (p = mv).

Illustrative background for Impulse = change in momentumIllustrative background for Impulse = change in momentum ?? "content

Impulse = change in momentum

  • The change in momentum of an object is equal to the impulse applied to it.
  • Impulse = change in momentum (Δp).
Illustrative background for Impulse equationIllustrative background for Impulse equation ?? "content

Impulse equation

  • Impulse = force x time.
  • Δp = F x t.
Illustrative background for Conservation of momentumIllustrative background for Conservation of momentum ?? "content

Conservation of momentum

  • The law of conservation of momentum says that momentum cannot be created or destroyed.
    • So, if two objects collide, the sum of momentum before collision = sum of momentum after collision.
Illustrative background for Change in momentum = mv - muIllustrative background for Change in momentum = mv - mu ?? "content

Change in momentum = mv - mu

  • Change in momentum = mv - mu, where m is mass, u is the initial velocity of an object and v is the final velocity of an object.

Force and Momentum Change

When a force acts on an object that is moving, or able to move, a change in momentum happens. Force equals the rate of change of momentum. This can be shown by combining two equations:

Illustrative background for Acceleration and momentumIllustrative background for Acceleration and momentum ?? "content

Acceleration and momentum

  • acceleration = change in velocity ÷ time taken.
    • a = Δv ÷ t.
Illustrative background for Force and accelerationIllustrative background for Force and acceleration ?? "content

Force and acceleration

  • Force = mass × acceleration.
    • F = m x a.
Illustrative background for Force = rate of change of momentumIllustrative background for Force = rate of change of momentum ?? "content

Force = rate of change of momentum

  • Combining the 2 equations we get F = m x Δv ÷ t.
  • F = m Δv ÷ t.
  • F = Δp ÷ t.
  • Force = change in momentum ÷ change in time.
  • In other words, force is equal to the rate of change of momentum.

Jump to other topics

1Space, Time & Motion

2The Particulate Nature of Matter

3Wave Behaviour

4Fields

4.1Circular Motion

4.2Newton's Law of Gravitation

4.3Fields

4.4Fields at Work

4.5Electric Fields

4.6Magnetic Effect of Electric Currents

4.7Heating Effect of Currents

4.8Electromagnetic Induction

4.9Power Generation & Transmission

4.10Capacitance

5Nuclear & Quantum Physics

6Measurements

Unlock your full potential with Seneca Premium

  • Unlimited access to 10,000+ open-ended exam questions

  • Mini-mock exams based on your study history

  • Unlock 800+ premium courses & e-books

Get started with Seneca Premium